JP5183431B2 - Oil recovery method for oil contaminated soil - Google Patents

Description

  The present invention relates to an oil recovery method for oil-contaminated soil that can efficiently recover oil from oil-contaminated soil.

By supplying air to the oil-contaminated area from the bottom of the oil-contaminated area of the oil-contaminated soil, the oil floating in the groundwater or the oil adhering to the soil particles or clogging between the soil particles rises to the groundwater surface. After forming an oil layer on the groundwater surface, the liquid accumulated in the recovery well is withdrawn. As a result, the groundwater level around the recovery well decreases, and the oil floating on the groundwater surface along with the groundwater moves laterally and flows into the recovery well. Can be recovered (see, for example, Patent Document 1).
JP 2007-245052 A

However, the oil on the groundwater surface has a slower flow than the groundwater, and if the groundwater level in the recovery well is lowered, the oil floating on the groundwater surface is difficult to move laterally (horizontal direction). There was a problem that oil could not be recovered efficiently because it was difficult to flow into the recovery well. In particular, when there is a wide range of underground oil-contaminated areas around the recovery well, the horizontal flow of the oil present at a location farther from the recovery well becomes slow, making it difficult for oil to flow into the recovery well. .
The present invention has been made in view of the above problems, and it is possible to quickly move the oil on the groundwater surface around the recovery well in the horizontal direction so that the oil easily flows into the recovery well. An oil recovery method for underground oil-contaminated soil that can be efficiently recovered is provided.

The oil recovery method for oil-contaminated soil according to the present invention forms a recovery well for recovering oil in an oil-contaminated part in the oil-contaminated soil, and uses a curved boring device to place the ground at an arbitrary position on the oil-contaminated soil. After forming a plurality of boreholes across the recovery well after passing between the ground surface and the oil-contaminated part from the surface to the ground, and reaching the ground surface at a position different from the arbitrary position, A perforated pipe provided with a plurality of holes penetrating the inner and outer surfaces of the pipe in the diameter-expanded hole in which the diameter of each bored hole is expanded so as to be positioned at a portion that passes through the oil-contaminated part. Water is injected into the perforated pipe embedded in the plurality of enlarged diameter holes and discharged from the hole of the perforated pipe toward the oil-contaminated part from above to the oil in the oil-contaminated part. While applying the water pressure and collecting the liquid in the recovery well, the recovery well Wherein the recovered oil that existed circumference.
Another oil recovery method for oil-contaminated soil according to the present invention forms a recovery well for recovering oil in an oil-contaminated part in oil-contaminated soil, and uses a curved boring device to select an arbitrary position of the oil-contaminated soil. A plurality of boreholes that reach the ground surface at a position different from the above-mentioned arbitrary position after extending below the oil-contaminated part from the ground surface to the ground and passing below the oil-contaminated part After the formation, the perforated pipe having a plurality of holes penetrating the inner surface and the outer surface of the pipe in the diameter-expanded holes obtained by enlarging the plurality of bore holes passes through the oil-contaminated portion. It is buried so that it is located in the part, water is injected into the perforated pipe buried in the plurality of enlarged diameter holes, and the oil is discharged by the water discharged from the hole of the perforated pipe toward the oil-contaminated part. Applying water pressure to the oil in the contaminated area from below and collecting the liquid in the recovery well. Accordingly, characterized in that to recover the oil that existed around the recovery well.
Still another oil recovery method for oil-contaminated soil according to the present invention is to form a recovery well for recovering oil in an oil-contaminated part in the oil-contaminated soil, and use a curved boring device to A boring hole that reaches the ground surface at a position different from the first arbitrary position after passing between the ground surface and the oil-contaminated part from the ground surface at any position to the ground is sandwiched between the recovery wells. After forming the plurality of bore holes, one of the perforated pipes having a plurality of holes penetrating the inner surface and the outer surface of the pipe in the diameter-expanded holes obtained by expanding the diameter of the plurality of bore holes is contaminated with oil. It is embedded so that it is located in the part that passes through the part, and is extended below the oil-contaminated part from the ground surface of the second arbitrary position of the oil-contaminated soil to the ground using a curved boring device. After passing under the oil-contaminated part, on the ground surface at a position different from the second arbitrary position After forming a plurality of boreholes reaching the recovery well, the other provided with a plurality of holes penetrating the inner surface and the outer surface of the tube in each diameter-expanded hole obtained by expanding each of the plurality of boreholes The perforated pipe is embedded so as to be located in a portion passing through the oil-contaminated part, and water is injected into one perforated pipe and the other perforated pipe embedded in the plurality of enlarged diameter holes. The recovery well is created by applying water pressure from above and below to the oil in the oil-contaminated part with water discharged from the holes of each perforated pipe in the direction of the oil-contaminated part and pulling up the liquid in the recovery well. It was characterized by recovering the oil that was present around .
Therefore, according to the oil recovery method of the oil-contaminated soil according to the present invention, from above the underground oil, from below the underground oil, or from above and below the underground oil, By applying hydraulic pressure to the oil, the oil on the groundwater surface around the recovery well can be moved quickly in the horizontal direction, making it easier for oil to flow into the recovery well and recovering oil efficiently. it can. In addition, water is injected from the ground into the oil-contaminated part through a hole in the perforated pipe that extends between the oil-contaminated part and the ground surface, so that water can be injected from the ground close to the oil-contaminated part. Since the hydraulic pressure loss can be reduced and the hydraulic pressure applied to the oil in the oil-contaminated part can be increased compared with the case where the oil recovery is performed, the oil recovery efficiency can be improved.

Best form 1
1 to FIG. 3 show the best mode 1 of the present invention, FIG. 1 is a view corresponding to the AA cross section of FIG. 3, and shows an oil recovery method for oil-contaminated soil, and FIG. It is a figure equivalent to -B cross section, and shows the oil recovery method of oil-contaminated soil, and FIG.

  With reference to FIG. 1, the structure of the oil recovery apparatus of underground oil-contaminated soil is demonstrated. The oil recovery device 1 includes a recovery well 2, a water pressure applying device 3, and a lifting device 4. X represents an unsaturated zone, Y represents a saturated zone, and L represents a groundwater level.

The recovery well 2 includes an excavation borehole 6 formed from the ground surface of the underground oil-contaminated soil 5 toward the underground oil-contaminated portion 8 and a perforated pipe for recovery inserted into the excavation borehole 6. 7.
The excavation hole 6 is formed at a depth at which the hole bottom 13 reaches below the oil-contaminated portion 8 of the oil-contaminated soil 5. That is, the excavation hole 6 is formed so as to pass from the ground surface of the oil-contaminated soil 5 through the oil-contaminated part 8 in the ground to reach below the oil-contaminated part 8. The position and depth of the oil-contaminated part 8 are examined by a preliminary boring survey.
The perforated tube 7 is formed, for example, by a bottomed tube having a circular cross section and having one end closed and the other end opened, and includes a plurality of holes 9 penetrating the inner surface and the outer surface of the tube on the wall of the tube. The hole 9 is formed by, for example, an elongated hole extending in the circumferential direction of the perforated tube 7. As the perforated tube 7, a perforated tube having a hole 9 only in a portion close to the oil-contaminated portion 8 is used. The perforated tube 7 may be formed by connecting a plurality of tubes, or may be formed by a single tube.
The perforated tube 7 is inserted into the excavation borehole 6 from the tube bottom 12 side. The diameter of the drill hole 6 and the outer diameter of the hole tube 7 are substantially the same so that the outer surface of the perforated pipe 7 and the inner wall surface 11 of the drill hole 6 are in contact.

The water pressure imparting device 3 includes a water storage tank 15, a pressure pump 16, a perforated pipe 17 for water injection, a connecting hose 18 that connects the water storage tank 15 and the pressure pump 16 so that they can communicate with each other, a drive power source 19 for the pressure pump 16, Is provided.
The perforated tube 17 is embedded in a boring hole formed by a known curved boring device. The method for embedding the perforated tube 17 in the borehole can be realized by a known method disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-293135. That is, using a curved boring device, after passing between the ground surface and the oil-contaminated portion 8 from the ground surface at an arbitrary position A of the oil-contaminated soil 5 to the ground, the ground at a position B different from the position A is obtained. After forming the boring hole that reaches the surface, remove the drilling bit attached to the tip of the rotating rod of the curved boring device that drilled the borehole, and attach the expanded drilling bit (called reamer) to the tip of the rotating rod . When the diameter of the drilling hole is increased from the outlet 26 of the boring hole at the B position to the inlet 25 of the boring hole at the A position, the diameter-extended drilling bit is adjusted in the direction of the drilling progress. By connecting the perforated tube 17 to the rear end, the perforated tube 17 can be embedded in the enlarged diameter hole 22 obtained by expanding the horizontal bore hole. The perforated tube 17 is formed by connecting a plurality of tubes. The perforated pipe 17 is embedded so that a perforated pipe provided with a plurality of holes 23 penetrating the inner and outer surfaces of the pipe on the wall of the perforated pipe is positioned only in a portion that passes through the oil-contaminated portion 8.
When viewed from the ground surface side, a plurality of perforated tubes 17 are provided, for example, so as to be positioned in parallel with each other with the recovery well 2 interposed therebetween (see FIGS. 2 and 3).
One end of a perforated pipe 17 extending from the inlet 25 of the enlarged diameter hole 22 to the ground and a discharge port of one pressurizing pump 16 are connected so as to communicate with each other, and a perforated hole extending from the outlet 26 of the enlarged diameter hole 22 to the ground. The other end of the pipe 17 is connected to the discharge port of the other pressurizing pump 16 so as to communicate with each other. In addition, only one of the one end or the other end of the perforated pipe 17 is connected to the pressurizing pump 16, and the pressurized water is supplied to the ground from only one end of the perforated pipe 17 or the other end. Also good.

  The lifting device 4 includes a lifting hose 31, a suction pump 32, a recovery tank 33, a connection hose 34 that connects the suction pump 32 and the recovery tank 33 so that they can communicate with each other, and a drive power source 35 for the suction pump. One end of the lifting hose 31 is connected to the suction port of the suction pump 32, and the other end of the lifting hose 31 is inserted into the liquid 36 in the recovery well 2. One end of the connection hose 34 is connected to the water intake port of the recovery tank 33, and the other end of the connection hose 34 is connected to the discharge port of the suction pump 32.

  With reference to FIG. 1, the oil recovery method of oil-contaminated soil is demonstrated. First, the range of the oil-contaminated part 8 and the underground depth of the oil-contaminated part 8 examined in the previous boring survey on the oil-contaminated soil 5 are confirmed, and the oil-contaminated part is located at the center of the range of the oil-contaminated part 8. The excavation borehole 6 having a depth deeper than 8 is formed, and the recovery hole 2 is formed in the excavation borehole 6 to form the recovery well 2. The imparting device 3 and the lifting device 4 are installed. Then, the oil recovery operation of the oil-contaminated soil 5 is performed by the water pressure application operation and the lifting operation.

  That is, by driving the pressurizing pump 16 of the water pressure applying device 3, the water in the water storage tank 15 is pressurized by the pressurizing pump 16, and is used for water injection extended between the oil contaminated portion 8 and the ground surface. By pouring water into the oil-contaminated part 8 from the ground through the hole 23 of the hole pipe 17, the water pressure P is applied to the upper surface of the oil-contaminated part 8 located around the recovery well 2, and the lifting device 4 The oil existing around the recovery well 2 is recovered in the recovery tank 33 by performing a lifting operation for lifting the liquid 36 in the recovery well 2.

According to the best mode 1, by applying the water pressure P to the upper surface of the oil-contaminated part 8 located around the recovery well 2, the oil-contaminated part 8 is pressed by the water pressure P on the upper surface of the oil-contaminated part 8. The oil becomes easier to move in the lateral direction. Therefore, the oil easily flows into the oil recovery well 2 and the oil can be recovered efficiently.
In addition, since the perforated pipe 17 for water injection is extended between the oil-contaminated part 8 and the ground surface, water can be injected from the ground close to the oil-contaminated part 8, compared with the case where water is injected from the ground surface. The water pressure loss can be reduced and the water pressure P applied to the oil in the oil contaminated part 8 can be increased. Accordingly, when the upper surface of the oil-contaminated part 8 is pushed with a larger water pressure P, the oil in the oil-contaminated part 8 is more easily moved in the lateral direction, so that the oil recovery efficiency can be further improved.

Best form 2
FIG. 4 shows an oil recovery processing apparatus and an oil recovery method for oil-contaminated soil.
In the best mode 2, the perforated pipe 17 for water injection is provided so as to extend below the oil-contaminated part 8 in the oil-contaminated soil 5 from the ground surface, and water is injected into the perforated pipe 17. The recovery operation of applying water pressure P from below to the oil in the oil-contaminated part 8 by the water discharged from the hole 23 of the perforated pipe 17 toward the oil-contaminated part 8 and pulling up the liquid 36 in the recovery well 2 By performing, the oil that was present around the recovery well 2 is recovered.
The configuration of the oil recovery device 1 used in the best mode 2 and the operations of the water pressure applying device 3 and the lifting device 4 are the same as those in the best mode 1.

According to the best mode 2, since the water pressure P is applied to the lower surface of the oil-contaminated part 8 from below the oil-contaminated part 8, the oil in the oil-contaminated part 8 easily moves in the lateral direction. Therefore, the oil easily flows into the oil recovery well 2 and the oil can be recovered efficiently.
Moreover, since the perforated pipe 17 for water injection is extended below the oil-contaminated part 8, water can be injected from the ground close to the oil-contaminated part 8, and water pressure loss is less than that when water is injected from the ground surface. Since the hydraulic pressure P applied to the oil in the oil contaminated part 8 can be increased, the oil recovery efficiency can be further improved.

Best form 3
The best mode 1 and the best mode 2 may be combined. That is, as shown in FIG. 5, the upper side of the oil-contaminated portion 8 is such that one of the perforated pipes 17 for water injection extends from the ground surface between the oil-contaminated portion 8 in the oil-contaminated soil 5 and the ground surface. The other perforated pipe 17 for water injection is provided below the oil-contaminated part 8 so as to extend below the oil-contaminated part 8 in the oil-contaminated soil 5 from the ground surface. Water is poured into the pipe 17 and the other perforated pipe 17 and discharged from the holes 23 of the perforated pipes 17 in the direction of the oil-contaminated part 8 to the oil in the oil-contaminated part 8 from above and below. The oil existing around the recovery well 2 is recovered by performing a recovery operation of applying the water pressure P and pulling up the liquid 36 in the recovery well 2.

  According to the best mode 3, a synergistic effect combining the effects of the best mode 1 and the best mode 2 can be obtained, and the oil recovery efficiency can be further improved.

The recovery perforated tube 7 may have a rectangular cross-sectional shape.
The shapes of the hole 9 of the recovery perforated pipe 7 and the hole 23 of the perforated pipe 17 for water injection are not limited.
The perforated pipe 17 for water injection may be configured such that one end is stopped in the ground and the other end is connected to the pressure pump 16 on the ground.

Sectional drawing which shows the oil collection | recovery method of oil-contaminated soil (best form 1). Sectional drawing which shows the oil collection | recovery method of oil-contaminated soil (best form 1). The top view which shows the oil collection | recovery method of oil-contaminated soil (best form 1). Sectional drawing which shows the oil collection | recovery method of oil-contaminated soil (best form 2). Sectional drawing which shows the oil collection | recovery method of oil-contaminated soil (best form 3).

Explanation of symbols

2 recovery wells, 5 oil-contaminated soil, 8 oil-contaminated parts, 17 perforated pipes, 23 perforated pipe holes,
36 Liquid in recovery well, P Water pressure.

Claims (3)

Form a recovery well for collecting oil in oil-contaminated soil in oil-contaminated soil, and use a curved boring device to move the ground surface and oil-contaminated portion from the ground surface at any position of oil-contaminated soil to the ground. After forming a plurality of boring holes that reach the ground surface at a position different from the above-mentioned arbitrary position after passing through between the recovery wells, each of the plurality of boring holes is expanded in each expanded diameter hole. A perforated pipe having a plurality of holes penetrating the inner and outer surfaces of the pipe is embedded in the pipe wall so as to be positioned at a portion passing through the oil-contaminated part, and embedded in the plurality of enlarged diameter holes. water perforated tube with adding water pressure from above the oil in the oil contaminated portion by water discharged toward the hole injection to the perforated tube in the direction of the oil pollution portions, fry pull the liquid in the recovery wells The oil that was present around the recovery well was recovered by performing the recovery operation. Oil recovery method of oil contaminated soil to be. Form a recovery well for collecting oil in oil-contaminated soil in oil-contaminated soil, and use a curved boring device from the ground surface at any position of oil-contaminated soil to the ground below the oil-contaminated portion. After extending under the oil-contaminated part and forming a plurality of boring holes that reach the ground surface at a position different from the above-mentioned arbitrary position across the recovery well, each of the plurality of boring holes is expanded. A perforated pipe having a plurality of holes penetrating the inner surface and the outer surface of the pipe in the diameter-expanded hole is embedded so as to be located in a portion passing through the oil-contaminated portion, and the plurality of diameter-expanded Water is injected into the perforated pipe embedded in the hole and discharged from the hole of the perforated pipe toward the oil-contaminated part. The oil that was present around the recovery well was recovered by performing a recovery operation to withdraw the liquid. Oil recovery methods of oil contaminated soil, characterized in that it has. Forming a recovery well for recovering oil in the oil-contaminated soil in the oil-contaminated soil, and using the curved boring device, the ground surface from the ground surface of the first arbitrary position of the oil-contaminated soil to the ground After forming a plurality of boring holes that reach the ground surface at a position different from the first arbitrary position after passing between the oil-contaminated portions, the diameter of each of the plurality of boring holes is increased. In each expanded diameter hole, one perforated pipe provided with a plurality of holes penetrating the inner and outer faces of the pipe is embedded in the diameter-expanded hole so as to be positioned at a portion passing through the oil-contaminated part, and a curved line. Using the boring device, after extending below the oil-contaminated part from the ground surface of the second arbitrary position of the oil-contaminated soil into the ground and passing under the oil-contaminated part, the second arbitrary position described above A plurality of boreholes that reach the ground surface at different positions are formed across the recovery well. Thereafter, the other perforated pipe provided with a plurality of holes penetrating the inner surface and the outer surface of the pipe in the diameter-expanded holes obtained by enlarging the plurality of bore holes passes through the oil-contaminated portion. The water is injected into one of the perforated pipes and the other perforated pipe embedded in the plurality of diameter-expanded holes so as to be located in the portion, and the direction of the oil-contaminated portion from the hole of each perforated pipe The oil that was present around the recovery well was recovered by applying water pressure from above and below to the oil in the oil-contaminated part with the water discharged toward An oil recovery method for oil-contaminated soil.

Images